The last time I went to a pop festival was in 1972, at Reading. The Faces were headlining. I worked my way to the front but I had overindulged in wacky baccy, gone wobbly and passed out, and was handed over the top of the crowd to medical people, who took me away. I came round backstage, sitting on a bench next to the late, great Viv Stanshall. 'All right, matey?' he said. All right? I'd say. It was much nicer out the back. More peaceful and yet much, much more exciting. Bands like Caravan and Pink Fairies flitted to and fro in satin loons, with a girl or two draped on a shoulder. Just having a girl attached to your arm seemed impossibly glamorous, let alone having properly long hair and playing in a band and smoking a spliff without feeling odd and ill.

I am not a natural festival-goer. Too many people, all strangers. Too much noise. The prospect feels more threatening than entertaining. But if festivals are your thing, then Glastonbury is the one.

I had not seen a picture of Michael Eavis before I met him, so did not know what to expect, but I found a remarkably fit, sprightly man looking at least 10 years younger than his 68, with one of those beards with no moustache. He laughs a lot, moves fast. Has a slight stammer. His farmhouse has roses growing up and around it, an old apple tree or two. I asked whether he gardened much. 'Oh no. Dairy farmers don't garden. Well, not round here anyway.' Eavis is, above all, a dairy farmer.

He drove me round his farm, showing me each field with the intimate detail that only someone who has worked it for years can appreciate. The big stage was up, looking like a rather beautiful sculpture, and the cattle grazed the other side of the trees. He showed me where the orchids grow - or try to, before the badgers eat the bulbs - and the field where the buttercups don't come back any more - 'too much slurry, I expect. We put no chemical fertiliser on our ground.' We saw huge piles of dead elm, and timber offcuts stacked for festival fires. We saw the field with trees planted to commemorate young people killed in car crashes or by cancer, whose parents had brought their ashes here and planted trees in their memory. Everywhere the grass grew long and lush, ready for silage-making, which would then leave a short sward for camping.

As we drove down the main field in front of the stage, Eavis told me that in 1997 Bob Dylan had turned up at the house instead of the proper backstage area. 'So I offered to take him down through the field and the crowds in his car.' What did he say to Dylan? 'Hello.' A roar of laughter. 'But people began pointing, so we had to cover him up with a blanket. By the time we got down there he must have been absolutely petrified. It was so embarrassing. But after all that, he still got up on stage and said: "This is like a dream come true to me." That was amazing. We had been trying to get him to come for years.'

The festival is called Glastonbury, but that doesn't give you any sense of place. Glastonbury is a few miles down the road. Eavis lives in Pilton, not far from Shepton Mallet. In the distance you can see Glastonbury Tor and on the horizon, when the light is right, the shimmer of the Bristol Channel. The farm is 400 acres, but he rents land from four farmers to more than double this area for the festival.

Eavis's land (heavy clay, good for oaks and grass) has not been ploughed for 100 years. The herd of 350 milking cows and 150 followers (those either too young to milk or not lactating) graze this grassy heaven. His great-grandfather bought the farm in 1894 and it has been farmed by his family, passed from father to son, since.

He went to sea at 15 to 'smarten himself up', but when he was 19 his father died and he came home to run the farm. His mother was a supply headmistress, a formidable character. What did she think of the festival? 'She thought it was a bit flaky at first, but she came round. She always stood by me.' He milked every day for 40 years until he got stomach cancer in 1994 and had to go into hospital. 'I told the cowman that I had to go in for an op and would miss a few weeks. But I felt so rotten that I didn't get back for three months.' He roars with laughter. 'When I was ready to come back I found the yield had gone up, so I let them do it after that.'

He tells me that he is first and foremost a farmer. They produce 10,000 litres of milk a day, all of which goes to make local cheddar. If he had to choose between the farm and the festival, which would it be? 'The farm. I've got that milking thing.' The leap from dairyman to world-famous promoter is not that big, really, especially when cows, feed, pop stars, punters and traders all come in and out of the same farm gate. But why the festival at all? 'Farming is lonely and I like working with people. They are so interesting. For example, McCartney's people rang up the other day wanting half a tonne of confetti. What on earth could they be doing with that? It's fascinating.' Eavis confesses that he has always had a soft spot for the travelling community - he finds them 'very entertaining. They are colourful, eccentric and interesting,' which is not a bad description of himself.

However, there is another vital element to his make-up that lies behind the festival. As a child, he went with his family to the Wesleyan chapel every Sunday. He still goes with his mother, who is now in her nineties. 'We enjoyed singing the hymns and all that sort of thing. It was all part of what we did.' The influence of the chapel is clearly right at the core of the Glastonbury Festival. The sense of family, of joining in and duty are clear in the way he runs it. But there is another element of chapel that has shaped the festival too. 'Chapel was always non-conformist and anti-everything. That's what we were. It was part of the community, but it wasn't church, it wasn't Tory and it was always taking on the establishment. The festival is just more non-conformity.'

Eavis is keen to stress the relationship between the village and the festival. 'The school provides stewards for the dance tents and earns £30,000 a year. We have provided a new working men's club and the land and stone for 10 houses to rent to local people. All the locals get free tickets.' And in conjunction with English Heritage the festival has raised more than £100,000 to help repair a tithe barn of staggering beauty.

Eavis took me round the village and showed me his buildings; he is evidently proud of what the festival has enabled him to put back into the community. He also took me to the chapel in the village and showed me the grave of his great-grandfather. I asked him if he would be buried there. 'I suppose so. I never think about dying - do you?' And he threw back his head and roared with laughter.